Update deprecated GitHub Actions to current versions (#19)

* Initial plan

* Update GitHub Actions to current stable versions

Co-authored-by: ManlyMarco <[email protected]>

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: ManlyMarco <[email protected]>

Author: Copilot

.github/workflows/main.yml

@@ -8,19 +8,19 @@ jobs:
     runs-on: windows-latest
 
     steps:
-    - uses: actions/checkout@master
+    - uses: actions/checkout@v4
     - name: Setup Nuget.exe
       uses: NuGet/[email protected]
     - name: Setup MSBuild.exe
-      uses: microsoft/setup-msbuild@v1
+      uses: microsoft/setup-msbuild@v2
     - name: Restore
       working-directory: .
       run: nuget restore
     - name: MSBuild
       working-directory: .
       run: msbuild /t:Build /p:Configuration=Release BepInEx.Debug.sln
     - name: Upload artifact
-      uses: actions/upload-artifact@v1.0.0
+      uses: actions/upload-artifact@v4
       with:
         name: BepInEx.Debug
         path: bin